"I can assure you that it will be a government that maintains its clear pro-European orientation," Pellegrini said in a statement.
"But mainly, I believe it will be a government that will calm the situation in our country," he added a day after he was tapped to replace close ally Robert Fico.
The EU member has been in political crisis since last month's killing of an investigative journalist who had been probing alleged ties between top politicians and Italian mafia.
The killing and Kuciak's article, published after he and his fiancee were found shot dead, had raised fresh concern about media freedom and corruption and sparked a wave of anti-government sentiment.
Fico resigned on Thursday after calls for snap elections from a junior coalition party, street protests and the opposition's decision to table a no-confidence vote against him.
But the veteran leftist will continue to chair the Smer-SD party, whose deputy is Pellegrini, leading analysts to believe that Fico will continue to pull the strings behind the scenes.
Organisers of the anti-government street protests this month continue to call for snap elections as well as a thorough and independent investigation of the journalist murder.
Organisers of the "For a decent Slovakia" protest, which is planned in 34 cities at home and 25 cities abroad, said Friday that the coalition government "humiliated and deceived the whole public."
"The new government, the way they perceive it, is not a real fulfillment of the demands of tens of thousands of people who took to the streets and stood up for a decent Slovakia," they added on their Facebook page.
The coalition government consists of the left-wing populist Smer-SD, plus two junior partners: the Most-Hid Hungarian minority party and the far-right Slovak National Party.
Eyewitness? Submit your stories now via social or:
Email: eyewitness@pulse.ng
